1、Designation: D3108 07D3108/D3108M 13Standard Test Method forCoefficient of Friction, Yarn to Solid Material1This standard is issued under the fixed designation D3108;D3108/D3108M; the number immediately following the designation indicatesthe year of original adoption or, in the case of revision, the
2、 year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the measurement of the kinetic frictional properties of a moving yarn in contact with
3、 a solidmaterial.NOTE 1For determining yarn-to-yarn friction, refer to Test Method D3412.1.2 This test method specifies a relative speed of 100 m/min. The test method may be used at other speeds, although with apossible change in precision and coefficient of friction.1.3 This test method covers the
4、measurement of the coefficient of kinetic friction between yarn and solid surface or surfacesof constant radius in the contact area. If a yarn of uniform value is used, comparisons of frictional properties of different solidmaterials can be made with relation to that yarn. If a given solid material
5、is used, comparisons of frictional properties of differentyarns, or yarns with different finishes, can be made with relation to that particular solid material.1.4 This test method specifically recommends wrap angles of 1.57, 3.14 and 6.28 radian (180 (90, 180 and 360), but other wrapangles may be us
6、ed, again with a possible change in precision and level. The angle of wrap should not be so great, especially foryarns having high coefficients of friction, that it causes the output tension to exceed the yield value for the yarn being tested.Also,in every case the angle of wrap should not be less t
7、han 1.57 rad (90).1.5 This test method has been applied to yarns having linear densities ranging between 101.5 and 80400 tex (9014 and 720denier)3600 denier and having coefficients of friction ranging between 0.1 and 0.51.0 but may also be used with yarns outsidethese ranges of linear densities and
8、coefficients of friction.1.6 The values stated in either SI units or inch-pound units are to be regarded separately as the standard. The values given inparentheses are for information only. stated in each system may not be exact equivalents; therefore, each system shall be usedindependently of the o
9、ther. Combining values from the two systems may result in non-conformance with the standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health pract
10、ices and determine the applicability of regulatorylimitations prior to use. Specific precautionary statements are given in Section 7.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD1907 Test Method for Linear Densit
11、y of Yarn (Yarn Number) by the Skein MethodD2258 Practice for Sampling Yarn for TestingD3412 Test Method for Coefficient of Friction, Yarn to YarnD4849 Terminology Related to Yarns and Fibers3. Terminology3.1 For all terminology relating to D13.58, Yarns and Fibers, refer to Terminology D4849.3.1.1
12、The following terms are relevant to this standard: coefficient of friction, friction, kinetic friction, radian, static fraction,wrap angle.1 This test method is under the jurisdiction of ASTM Committee D13 on Textiles and is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Curren
13、t edition approved Jan. 1, 2007July 1, 2013. Published January 2007August 2013. Originally approved in 1972. Last previous edition approved in 20012007 asD3108 01.D3108 07. DOI: 10.1520/D3108-07.10.1520/D3108_D3108M-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactAS
14、TM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been mad
15、e to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copy
16、right ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 For all other terminology related to textiles, refer to Terminology D123.4. Summary of Test Method4.1 Alength of yarn is run at known speeds and in contact with either single or multiple
17、 friction surfaces using a specified wrapangle. (See Fig. 1.) The yarn input and output tensions are measured, and the coefficient of friction is calculated by means ofAmontons law (see 11.4). Alternatively, apparatus is used in which the ratio of output tension to input tension is measuredallowing
18、the coefficient of friction to be indicated directly.5. Significance and Use5.1 Test Method D3108 for the determination of kinetic friction between yarn and solid materials may be used for theacceptance testing of commercial shipments of yarn, but caution is advised since between laboratory precisio
19、n is known to be poor.Comparative tests as directed in 5.1.1 may be advisable.5.1.1 If there are differences or practical significance between reported test results for two laboratories (or more), comparativetests should be performed to determine if there is a statistical bias between them, using co
20、mpetent statistical assistance. As aminimum, test samples that are as homogenous as possible, drawn from the material from which the disparate test results wereobtained, and randomly assigned in equal numbers to each laboratory for testing. The test results from the two laboratories shouldbe compare
21、d using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If a bias is found,either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the knownbias.5.2 The frictional properties of texti
22、le yarns and of machinery components such as yarn guides are of general interest and havemany applications. Because the frictional properties of yarns will affect the performance and life of yarn guides, sewing andknitting needles, and other contact surfaces, the modifying effects of surface finishe
23、s and lubricants are of special interest.Frictional properties also affect the quality and performance properties of yarns and subsequently of products made from them.Asa consequence, frictional properties are of interest in research, control, and product design.5.3 It is stressed that there is no c
24、oefficient of friction for a single body such as a yarn or a surface. A coefficient of frictionmeasures the interaction between two bodies or elements such as a yarn running over a surface.5.4 Although this method lays down standardized conditions of test, nonstandard conditions may be used for rese
25、arch ordiagnosis but should be reported as such.5.5 This method covers determination of the mean friction over a specified length of yarn.5.6 Additional information has been reported in the literature.3,4,53 Olsen, J.S., “Frictional Behaviour of Textile Yarns,” Textile Research Journal, Vol 39 No 1,
26、 1969, pp 3137.4 Lyne, D.G., “Dynamic Friction Between Cellulose Acetate Yarn and a Metal Cylinder,” Journal of the Textile Institute , Vol 46, 1955, p 112.5 Rubenstein, C., “Review of the Factors Influencing the Friction of Fibres, Yarns and Fabrics,” “Wear” Vol 2, 195859, p 296.FIG. 1 Schematic Di
27、agram of Angle of WrapD3108/D3108M 1326. Apparatus6.1 Friction Testing Apparatus (Indirect)6 (Fig. 2)Apparatus in which the input tension is measured or controlled to a setvalue, the output tension is measured, and the coefficient of friction is calculated within or outside the apparatus.6.1.1 Yarn
28、Tension Input ControlA means of controlling the yarn input tension to the nearest 61 mN (60.1 gf).60.1 gf. Ademand-fed apparatus with a fixed weight is suitable.6.1.2 Yarn Input Tension MeasurementThe yarn input tension is measured to within 61 mN (60.1 gf)60.1 gf using asuitable tension gage produc
29、ing an electrical signal. The signal is recorded as mN (gf)gf, or is used in combination with the yarnoutput tension measurement to calculate the coefficient of friction.6.1.3 Yarn Output Tension MeasurementThe yarn output tension is measured to within 61 mN (60.1 gf)60.1 gf using asuitable tension
30、gage producing an electrical signal. The signal is recorded as mN (gf)gf or is used in combination with the yarninput tension measurement to calculate the coefficient of friction. A suitable chart recorder may be used.6.2 Friction Testing Apparatus (Direct) (Fig. 3)Apparatus in which the ratio of ou
31、tput to input tensions is established directlyand the coefficient of friction indicated on a scale or display. The comparison may be mechanical.6.2.1 Yarn Tension Input ControlSince this type of apparatus automatically derives the ratio of output-to-input-tension, closecontrol of input tension is no
32、t usually required. However, because the absolute level of input tension can affect the measuredcoefficient of friction for certain yarns, particularly low-twist yarns, the general level of input tension should be preset, for examplewith a dead weight disk tensioner.6.2.2 Coeffcient of Friction Indi
33、catorThe nature of this will depend on the instrument being used. Typically, a pointer or achart recorder pen is displaced by the movement of the components that bring the system into balance and the product of the inputtension and the distance from the axis equals the product of the output tension
34、and the distance from the axis (see Fig. 3).6.3 Friction Surface, may be changeable on some equipment.6.3.1 Standard Friction SurfaceFriction surfaces having a diameter of 0.5 in. (12.7 mm) 12.7 mm for yarns having lineardensities ranging from 1.5 to 80 tex, or 0.79 in. 20.0 mm for yarns having line
35、ar densities ranging from 80 to 400 tex, and achrome surface of 40.03 to 6 m roughness. The use of one, two, or three pins in sequence has been found satisfactory althoughthere may be a difference in the results (theoretically only the total angle of wrap and not the number of pins should affect the
36、results). (See 12.3.4).6.3.2 Other Friction SurfacesUnless the apparatus has a friction surface that cannot be altered, friction surfaces of differentmaterials, sizes, and surface finish may be used but must be specified in the report (see 12.3.4).6.4 Drive System, consisting of a controlled speed y
37、arn transporting device with appropriate controls to record and adjust thelinear or throughput speed. Generally, a speed of less than 300400 m/min has been found preferable. The yarn transporting deviceshould be constructed to eliminate yarn slippage by the use of high-friction surface.6 Equipment m
38、eeting these requirements may be commercially obtained from Lawson Hemphill (Sales) Inc., PO Drawer 6388, Spartanburg, SC 29304.FIG. 2 Schematic Diagram of Typical Yarn Friction Measuring Apparatus, Indirect TypeD3108/D3108M 1336.5 Cotton Yarn For CleaningA thoroughly scoured cotton yarn that is hig
39、hly absorbent (see section 10.2.2 and Annex A1).6.6 SolventSee 10.2.7. Hazard7.1 Refer to the manufacturers material safety data sheet for information on storage, handling, use, and disposal of chemicalsused in this test method.8. Sampling8.1 Lot SampleAs a lot sample for acceptance testing, take at
40、 random the number of shipping units directed in an applicablematerial specification or other agreement between the purchaser and the supplier, such as an agreement to use Practice D2258.Consider shipping cases or other shipping units to be the primary sampling units.NOTE 2An adequate specification
41、or other agreement between the purchaser and the supplier requires taking into account the variability betweenshipping units, between packages or ends within a shipping unit, and between specimens from a single package so as to provide a sampling plan witha meaningful producers risk, consumers risk,
42、 acceptable quality level, and limiting quality level.8.2 Laboratory SampleAs a laboratory sample for acceptance testing, take at random from the each shipping unit in the lotsample the number of packages or ends directed in an applicable material specification or other agreement between the purchas
43、erand the supplier such as an agreement to use Practice D2258. Preferably, the same number of packages should be taken from eachshipping unit in the lot sample. If differing numbers of packages are to be taken from shipping units in the lot sample, determineat random which shipping units are to have
44、 each number of packages drawn.8.3 Test SpecimensTest one specimen from each package in the laboratory sample.9. Conditioning9.1 Preparation of Test PackagesRemove sufficient yarn from the test packages to avoid testing nonrepresentative layers. Ifin doubt, remove about 10 % of the length of yarn on
45、 the package.9.2 The strand to be tested must have a uniform moisture content along its length. Atmospheric conditions must therefore bestable and the strand must be in equilibrium with the prevailing atmosphere. To satisfy this condition, testing should be carried outafter thorough conditioning in
46、the standard atmosphere for testing textiles.9.3 PreconditioningPrecondition packages of yarn for at least 3 h in an atmosphere with a relative humidity between 5 and25 % and a temperature not exceeding 50C (120F).9.3 ConditioningCondition the preconditioned packages of yarn in the standard atmosphe
47、re for testing textiles (relativehumidity 65 6 2 % and temperature 21 6 1C (70 6 2F) in moving air until it has reached moisture equilibrium for testingPrecondition and condition the specimens as directed in Practice D1776.FIG. 3 Schematic Diagram of Typical Yarn Friction Measuring Apparatus, Direct
48、 TypeD3108/D3108M 13410. Procedure10.1 Test all specimens in the standard atmosphere for testing textiles which is 21as directed in Practice D17766 1C (70 62F) and 656 2 % relative humidity10.2 Prior to each test, thoroughly clean the friction elements, input rolls, and any other surfaces with which
49、 the yarn comesin contact up to and including the friction element, using one of the following:10.2.1 A solvent which contains no trace oils, orNOTE 3Precaution: If solvent is used, appropriate health and safety precautions must be taken. (See Section on Hazards)10.2.2 A thoroughly scoured cotton yarn7 that is highly absorbent used as a cleaning yarn. See Annex A1 for details.10.3 Check the surface properties of the friction elements for wear, gouging, or channeling. Some textile yarns, specificallyglass, stainless steel,
